package com.sky.aspect;

import com.sky.annotation.AutoFill;
import com.sky.constant.AutoFillConstant;
import com.sky.context.BaseContext;
import com.sky.enumeration.OperationType;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;

import java.lang.reflect.Method;
import java.time.LocalDateTime;
import java.util.function.LongFunction;

/**
 * 自定义填充公共字段的切面
 */
@Aspect
@Component
@Slf4j
public class AutoFillAspect {

    //指定切入点
    @Pointcut("execution(* com.sky.mapper.*.*(..)) && @annotation(com.sky.annotation.AutoFill)")
    public void autoFillPointCut() {}

    //前置通知，用于实现自动填充
    @Before("autoFillPointCut()")
    public void autoFill(JoinPoint joinPoint) {
        log.info("开始进行自动填充");

        // 1. 获取当前被拦截方法的签名对象
        MethodSignature signature = (MethodSignature) joinPoint.getSignature();

        // 2. 从签名中获取方法对象
        Method method = signature.getMethod();

        // 3. 从方法对象上获取我们自定义的 @AutoFill 注解
        AutoFill autoFill = method.getAnnotation(AutoFill.class);

        // 4. 获取注解中定义的数据库操作类型
        OperationType operationType = autoFill.value();

        // 5. 获取当前被拦截的参数
        Object[] args = joinPoint.getArgs();
        if (args == null || args.length == 0) {
            return;
        }
        Object entity = args[0];

        // 6. 准备赋值的数据
        LocalDateTime now = LocalDateTime.now();
        Long currentId = BaseContext.getCurrentId();



        // 7.根据操作类型，为对应的字段赋值
        if (operationType == OperationType.INSERT) {
            try {
                Method setCreateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_TIME, LocalDateTime.class);
                Method setCreateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_USER, Long.class);
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);

                //通过反射为当前对象属性赋值
                // 通过反射调用setter方法
                setCreateTime.invoke(entity, now);
                setCreateUser.invoke(entity, currentId);
                setUpdateTime.invoke(entity, now);
                setUpdateUser.invoke(entity, currentId);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        } else if (operationType == OperationType.UPDATE) {
            try {
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);

                //通过反射为当前对象属性赋值
                // 通过反射调用setter方法
                setUpdateTime.invoke(entity, now);
                setUpdateUser.invoke(entity, currentId);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }


    }

}